Overview Of Core Heat Conduction Path Schemes For Power Battery Systems Of New Energy Vehicles

In battery thermal management, another design focus is on the planning of heat conduction paths, which not only affects the thermal management efficiency and volume utilization of the entire package, but also affects the cost of the entire package.
The path through which heat is transferred from the battery core to the outside of the battery pack is called a heat conduction path, and the heat conduction interface material is arranged within the heat conduction path. According to different battery technology schemes, the location of the thermal conductive interface material TIM varies. Here, the current mainstream approach is viewed from the location relationship between the battery core and the thermal conductive interface material TIM.
(a) There are modules, with water cooled plates arranged inside the box, and thermal conductive interface materials arranged inside the shell and on the outer surface, respectively in contact with the electrical core and water cooled plate. This is the main solution during the module technology period, such as SAIC Mingjue, Roewe Marvel X, General Bolt EV, Ford Mach-e, VW MEB, Audi A6 PHEV, etc;
(b) There are modules, with water cooling plates arranged outside the box and inside the protective plate. This is also known as integrated liquid cooling of the box, such as IPace and Audi e-tron
(c) There is no module, and the BYD CTP scheme is adopted. The water cooled plate is arranged on the top, and the thermal conductive interface material is arranged between the electric core and the cold plate. The representative cases are BYD Han CTP, FAW Hongqi E-QM5, Dolphin, and Song Plus DM-i.
(d) There is a module, which is a bottomless plate type, so that the electrical core is directly in contact with the water cooled plate, and the thermal conductive interface material is arranged between the two; Representative cases such as Model 3 (Picture | Configuration | Inquiry) square core version, BMW ix, and BAIC EU5; In addition, for Tesla's cylindrical core scheme, a thermal conductive structural adhesive is arranged between the Model 3/Y serpentine water cooling pipe and the core, which also belongs to this scheme;
(e) There is a module, and the liquid cooled plate is integrated with the module. This solution represents a Benz EQC (Picture | Configuration | Inquiry), with thermal conductive interface materials arranged between the battery core and the cold plate;
(f) There are modules, where the liquid plate is separated from the module, but there is no thermal conductivity interface between the cold plate and the module, and the cold plate is in close contact with the bottom of the module (generally, there is an elastic support at the bottom of the cold plate). This is the case with BMW i3, BMW X1PHEV, and others.
The biggest reliance on the planning of the heat transfer path is on the electrical core. If the electrical core itself has a new breakthrough in thermal safety, it will bring a new impact on the entire thermal management; Another major dependency is the overall consideration of battery thermal management by vehicle companies. In fact, the key to temperature control during the entire battery life cycle is three scenarios: (1) during fast charging; (2) Low temperature use; (3) Driving at high speed for a long time. If we can skillfully solve the temperature control of these three scenarios, it will definitely bring a new improvement to the battery system design, and the Mercedes EQXX may be an example.